Conventionally, in a diesel engine or the like, to inject high-pressure fuel efficiently, various accumulator fuel injection devices which use an accumulator (a common rail) have been proposed.
As a fuel supply pump which is applicable to such an accumulator fuel injection device, there has been adopted a fuel supply pump which includes a cam which is rotatably integrally mounted on a cam shaft which is rotated by driving an engine, a plunger which is elevated due to the rotation of the cam, a tappet structural body which transmits the rotation of the cam to the plunger as a rising force, and a return spring which imparts a lowering force to the tappet structural body and the plunger. Here, as the tappet structural body which is applicable to the fuel supply pump, as shown in FIG. 19, there has been proposed a tappet structural body which is constituted of a tappet body portion which includes a cylindrical slide portion which is slidably inserted in a cylindrical slide surface and a roller holding portion which extends toward one axial end of the slide portion, a pin which has both ends thereof held by the roller holding portion of the tappet body portion, and a roller which is rotatably held by the pin (see Patent Document 1, for example).
[Patent Document 1] JP-A-2001-317430 (FIG. 2)